Driver circuit, electro-optical device, electronic instrument, and drive method

Abstract

A driver circuit includes a first output buffer BUF 1 which drives a data line of an electro-optical device based on grayscale data, and a first precharge circuit PC 1 which precharges an output line of the first output buffer BUF 1 . The first precharge circuit PC 1 supplies a first precharge voltage to the output line in a first precharge period in a drive period. In a second precharge period after the first precharge period, the first precharge circuit PC 1 supplies a high-potential-side power supply voltage, a low-potential-side power supply voltage, or the first precharge voltage to the output line based on higher-order two-bit data of the grayscale data. The first output buffer BUF 1 drives the output line based on a grayscale voltage corresponding to the grayscale data after the second precharge period.

1 . A driver circuit for driving a data line of an electro-optical device, the driver circuit comprising: 
 an output buffer which drives the data line based on grayscale data; and    a precharge circuit which precharges an output line of the output buffer electrically connected with the data line;    the precharge circuit supplying a first precharge voltage between a high-potential-side power supply voltage and a low-potential-side power supply voltage of the output buffer to the output line in a first precharge period in a drive period;    the precharge circuit supplying the high-potential-side power supply voltage of the output buffer, the low-potential-side power supply voltage of the output buffer, or the first precharge voltage to the output line based on higher-order two-bit data of the grayscale data in a second precharge period after the first precharge period; and    the output buffer driving the output line based on a grayscale voltage corresponding to the grayscale data after the second precharge period.    
   
   
       2 . The driver circuit as defined in  claim 1 , wherein the first precharge voltage is generated as an average value using the voltage to which the output line of the output buffer is precharged and a precharge voltage to which an output line of an output buffer other than the output buffer is precharged.  
   
   
       3 . A driver circuit for driving data lines of an electro-optical device, the driver circuit comprising: 
 first to Pth (P is an integer of two or more) output buffers which drive the data lines based on grayscale data;    first to Pth precharge circuits which precharge output lines of the output buffers electrically connected with the data lines; and    first to (P-1)th switch devices which electrically connect the output lines of the first to Pth output buffers;    the first to Pth precharge circuits precharging the output lines of the first to Pth output buffers by electrically connecting the output lines of the first to Pth output buffers through the first to (P-1)th switch devices, and the first to Pth output buffers then driving the data lines based on the grayscale data.    
   
   
       4 . The driver circuit as defined in  claim 3 , 
 wherein, in a first precharge period in a drive period, at least one of the first to Pth precharge circuits supplies a high-potential-side power supply voltage of the first to Pth output buffers to the output line of the output buffer, the remaining precharge circuits supply a low-potential-side power supply voltage of the first to Pth output buffers to the output lines of the output buffers, and the first to (P-1)th switch devices are then set in a conducting state to set voltages of the output lines of the first to Pth output buffers at a first precharge voltage;    wherein, in a second precharge period after the first precharge period, the first to Pth precharge circuits supply the high-potential-side power supply voltage, the low-potential-side power supply voltage, or the first precharge voltage to the output lines of the first to Pth output buffers based on higher-order two-bit data of the grayscale data; and    wherein the first to Pth output buffers drive the output lines based on the grayscale data after the second precharge period.    
   
   
       5 . An electro-optical device comprising: 
 a plurality of scan lines;    a plurality of data lines;    a plurality of pixels;    a scan line driver circuit which scans the scan lines; and    the driver circuit as defined in  claim 1  which drives the data lines.    
   
   
       6 . An electro-optical device comprising: 
 a plurality of scan lines;    a plurality of data lines;    a plurality of pixels;    a scan line driver circuit which scans the scan lines; and    the driver circuit as defined in  claim 3  which drives the data lines.    
   
   
       7 . An electronic instrument comprising the electro-optical device as defined in  claim 5 .  
   
   
       8 . An electronic instrument comprising the electro-optical device as defined in  claim 6 .  
   
   
       9 . A drive method for driving a data line of an electro-optical device, the method comprising: 
 supplying a first precharge voltage to an output line of an output buffer for driving the data line in a first precharge period in a drive period;    supplying a high-potential-side power supply voltage of the output buffer, a low-potential-side power supply voltage of the output buffer, or the first precharge voltage to the output line based on higher-order two-bit data of grayscale data in a second precharge period after the first precharge period; and    causing the output buffer to drive the output line based on a grayscale voltage corresponding to the grayscale data after the second precharge period.    
   
   
       10 . A drive method for driving a driver circuit including first to Pth (P is an integer of two or more) output buffers which drive data lines of an electro-optical device based on grayscale data, first to Pth precharge circuits which precharge output lines of the output buffers electrically connected with the data lines, and first to (P-1)th switch devices which electrically connect the output lines of the first to Pth output buffers, the method comprising: 
 in a first precharge period in a drive period, causing at least one of the first to Pth precharge circuits to supply a high-potential-side power supply voltage of the first to Pth output buffers to the output line of the output buffer, causing the remaining precharge circuits to supply a low-potential-side power supply voltage of the first to Pth output buffers to the output lines of the output buffers, and then setting the first to (P-1)th switch devices in a conducting state to set voltages of the output lines of the first to Pth output buffers at a first precharge voltage;    in a second precharge period after the first precharge period, causing the first to Pth precharge circuits to supply the high-potential-side power supply voltage, the low-potential-side power supply voltage, or the first precharge voltage to the output lines of the first to Pth output buffers based on higher-order two-bit data of the grayscale data; and    causing the first to Pth output buffers to drive the output lines based on the grayscale data after the second precharge period.